I have some Java functions for doing AES encryption, one for a string, and one for a file

private static final String AES_CIPHER_METHOD = AES;



public static SecretKeySpec createAesKeySpec(byte[] aesKey) {

    return new SecretKeySpec(aesKey, AES_CIPHER_METHOD);

}



public static String aesEncrypt(String data, SecretKeySpec aesKeySpec) throws EncryptionException {

    try {

        Cipher aesCipher = Cipher.getInstance(AES_CIPHER_METHOD);

        aesCipher.init(Cipher.ENCRYPT_MODE, aesKeySpec);

        byte[] encVal = aesCipher.doFinal(data.getBytes(UTF8));

        return new BASE64Encoder().encode(encVal);

    } catch (NoSuchAlgorithmException | NoSuchPaddingException | InvalidKeyException | IOException | BadPaddingException| IllegalBlockSizeException e) {

        throw new EncryptionException(e.getMessage(), e);

    }

}



public static void aesEncryptFile(File in, File out, SecretKeySpec aesKeySpec) throws EncryptionException {

    try {

        Cipher aesCipher = Cipher.getInstance(AES_CIPHER_METHOD);

        aesCipher.init(Cipher.ENCRYPT_MODE, aesKeySpec);



        try (InputStream inputStream = new FileInputStream(in)) {

            try (OutputStream outputStream = new CipherOutputStream(new FileOutputStream(out), aesCipher)){

                IOUtils.copy(inputStream, outputStream);

            }

        }

    } catch (InvalidKeyException | NoSuchAlgorithmException | NoSuchPaddingException | IOException e){

        throw new EncryptionException(e.getMessage(), e);

    }

}

I also have some tests to output some test data

private static final String KEY_STRING = DpiA4l0gvb7biWZtiN6Vjg==;



private SecretKeySpec createKeySpec() {

    byte[] keyBytes = new Base64().decode(KEY_STRING.getBytes());

    return EncryptionUtils.createAesKeySpec(keyBytes);

}



public void testAesEncryptString() throws EncryptionException {

    String encryptedData = EncryptionUtils.aesEncrypt(A normal string, createKeySpec());

    System.out.println(encryptedData); //outputs 3XLwlSHWLm98teIoIS6QTA==

}



public void testAesEncryptStringFile() throws EncryptionException, IOException {

    File newFile = new File(FilenameUtils.concat(System.getProperty(java.io.tmpdir), myFile.txt));

    FileUtils.writeStringToFile(newFile, A string in a file);



    File encryptedFile = new File(FilenameUtils.concat(System.getProperty(java.io.tmpdir), myFile_encrypted.txt));



    EncryptionUtils.aesEncryptFile(newFile, encryptedFile, createKeySpec());

}

I now need to implement decryption in javascript.

I have managed to successfully decrypt the plain string using crypto-js, however, I just cant get the file part working, and I cant quite see what is wrong

var base64Key = DpiA4l0gvb7biWZtiN6Vjg==;

var key = CryptoJS.enc.Base64.parse(base64Key);



var aesOptions = {

    mode: CryptoJS.mode.ECB,

    padding: CryptoJS.pad.Pkcs7

};



var decryptedData = CryptoJS.AES.decrypt( 3XLwlSHWLm98teIoIS6QTA==, key, aesOptions);

var decryptedText = decryptedData.toString( CryptoJS.enc.Utf8 );

console.log( decryptedText =  + decryptedText ); //CORRECT outputs A normal string



var encryptedFilename = https://dl.dropboxusercontent.com/u/30823828/myFile_encrypted.txt;

$.get(encryptedFilename, function(data){

    console.log(encrypted file content, data);

    var encryptedData = CryptoJS.enc.Base64.parse(data);

    var decryptedData = CryptoJS.AES.decrypt( encryptedData, key, aesOptions);

    var decryptedText = decryptedData.toString( CryptoJS.enc.Utf8 );

    console.log( decrypted file content =  + decryptedText ); //INCORRECT outputs  SHOULD output A string in a file

});

link to jsfiddle - http://jsfiddle.net/pKNzV/46/